import java.util.Scanner;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 86156
 * Date: 2023-04-09
 * Time: 11:49
 */

// 对称字符串 123321
public class builderTest {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str1 = scanner.next();
        StringBuilder sb = new StringBuilder();
        String str = sb.append(str1).reverse().toString();
        if(str1.equals(str)){
            System.out.println("是");
        }else{
            System.out.println("不是");
        }
    }
    public static void main1(String[] args) {
        Scanner scanner = new Scanner(System.in);

        String str = scanner.next();

        int left = 0;
        int right = str.length()-1;

        while(left<right){
            if(str.charAt(left) == str.charAt(right)){
                left++;
                right--;
            }else{
                System.out.println("不是");
                return;
            }
        }
        System.out.println("是");
    }
}
